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Taco Cowboy writes "For the past year or so, a tiny scale farming experiment in has been carried out in the desert field of Qatar, using only sunlight and seawater. From the article: 'A pilot plant built by the Sahara Forest Project (SFP) produced 75 kilograms of vegetables per square meter in three crops annually (or 25 kilograms per square meter, per crop)' If the yield level can be maintained, a farm of the size of 60 hectares would be enough to supply the nation of Qatar with all the cucumbers, tomatoes, peppers, and egglants that it needs. 'The project will proceed to the next stage with an expansion to 20 hectares, to test its viability into commercial operation.'"

I don't know about cucumbers, but given some tomatoes and eggplant and you're well on your way to a nice stew. Just add some goat, onion, garlic, cumin, salt and pepper and you'll feed the family for a week!

Cucumbers and eggplant are a significant source of pretty much zero vitamins and minerals. I wonder if they are particularly robust in the scorched soil because they require relatively few nutrients... ?

Radishes - both the bulbs and the greens - are just fine (though spicy) in salads.

Also: My chickens LOVE them, though they like grain, chard, bugs, and blueberries progressively better. (I'm not sure where mice and shrews fit into the hierarchy but I'm sure they'd be near the more-desirable end.)

A single large radish, tossed the flock, is the starting move in a game of chicken soccer. The radish quickly takes on the appearance of a soccer ball as they take enough bites to make it dotted red-and-white all

They're not exactly high calorie. Perfectly reasonable choices in terms of growing nice food ('value creation' as they put it), though I can't help wondering if they'll get the mother of all red spider mite infestations. Arab countries have bought huge amounts of African farmland in attempt to gain some food security, and if you assume it's for that purpose instead then you might have expected different choices. Still not radishes, though.

When you are setting up a new industry you go with high profit, then someday when the business model is proven out and streamlined you can do something that is much lower profit.

As it is if they want high calorie they could buy a load of grain from the US for 1/100 the price they could grow in the desert. Vegtables on the other hand don't ship as easily as grain, so growing them locally would make more sense as customers pay a premium for the higher quality.

Although I fully support and applaud this effort, this is not the only way to get the job done. Permaculture design can achieve similar results with much smaller inputs, as described in this video. [youtube.com]

The most important concept of permaculture is water management. If you only get 8" of rain per year and it all comes within a 3-week window, you'd better have your land "sculpted" to optimize retention of water on the surface for as long as possible. Such improvements last for generations, and continually add fertility and biodiversity to the land.

If we seriously applied these principles worldwide, we could make the entire globe flood-proof and drought-proof in less than a decade. Seriously.

For example, check the before & after photos in Green Gold [youtube.com] or in this TED Talk [youtube.com] by Allan Savory. These amazing transformations happen in just a few years. Imagine what would be possible over the long term.

Why were those vegetables chosen instead of others? Why not radishes, etc?

Probably because all of those vegetables can be grown in a similar climate as each other, all of them have very similar growing techniques where the plant can be placed in a wire cage or mesh that supports vertical growth.

Each of those plants have broad leaves, can be cultivated to thrive in lower water, and can be cultivated to require a relatively small footprint.

When you are going to grow a bunch of water-loving plants in the desert, you are going to want tall self-shading structures. If you look at their greenhouses in the article you can see that vertical space is available but horizontal space is a premium.

I happen to live in a desert and have grown three of those four plants for decades. They grow well together.

This is about growing food people will consume. If in the same shoes I would choose the same crops. Not because they are the most efficient, not because they are the best for you. But because it's the income that will allow the plant to continue to grow food. Local food.

And it's that last two words that matter most. Local food. As in the amount of oil used to transport the food from a far off land is drastically reduced.

Even if the crops are not the best source of nutrition they are still better for you in the long run. Simply because the cost in carbon and energy is so low.

And to top it off this is only the start. In the future when the tech becomes cheaper and easier to implement the market is easier for people like your self to grow a radish or 6.

And it's that last two words that matter most. Local food. As in the amount of oil used to transport the food from a far off land is drastically reduced.

Even if the crops are not the best source of nutrition they are still better for you in the long run. Simply because the cost in carbon and energy is so low.

And to top it off this is only the start. In the future when the tech becomes cheaper and easier to implement the market is easier for people like your self to grow a radish or 6.

But something like 86% or more of the energy/carbon budget for food production is at the point of production. Only 5% in some studies is used for transportation. Hey, every bit helps, but transportation costs (energy and dollars) are not particularly high for most foods.

>With that said, these green houses are well situated to minimize heating costs

I suspect heating costs is not high on their priority list - they're in a relatively low latitude (25*) coastal desert, heat is unlikely to be in short supply, the greenhouse is almost certainly to retain moisture. In fact they're not even using solar power for desalination, except indirectly - from TFA:

At one end, salt water is trickled over a gridlike curtain so that the prevailing wind blows the resulting cool, moist air over the plants inside. This cooling effect allowed the Qatar facility to grow three crops per year, even in the scorching summer. At the other end of the greenhouse is a network of pipes with cold seawater running through them. Some of the moisture in the air condenses on the pipes and is collected, providing a source of fresh water.

On the what people want, that's fair, but I think what people end up wanting in terms of food is driven more by what people have to sell than you're giving credit. Advertising and creating demand. Americans didn't have an unusual craving for corn and high fructose corn syrup until someone realized that corn subsidies meant corn was really cheap to make.

If you make foods that can be grown cheaply in the desert, I'm sure someone will come along and find out how to make people want to eat it. And you can

If you have to cool it to transport it, then that's part of the transportation cost. The energy to cool something doesn't come for free. The fact that it costs a tremendous amount of energy to cool stuff doesn't alter the basic problem except to make it more dire.

I am very curious about the economics of this type of farming. (Note, I am not necessarily a skeptic). The cost of the water is obviously a driver to make sure the maximum amount of water is recycled. I wonder if they use hydroponics?

Greenhouses are used at large scale elsewhere with a lot of success. The Netherlands has a large area of greenhouses to produce tomatoes and peppers (and a lot more). There, the water is not a bottleneck, but sunlight is. So, lamps are used. I guess that is just as costly, showing that the economics of a greenhouse are not necessarily a problem.

The arab countries never really worried about energy efficiency in the past. The problem there is every drop of drinking water is effectively sourced from desalination. The town water in Qatar tastes absolutely crap and even the hotels typically provide 2L bottled water bottles in the rooms (can't wait to hear the complains from the upcoming world cup).

This creates a very interesting problem for farming in the desert which looks absolutely fascinating on Google Maps [goo.gl]

The Netherlands has a large area of greenhouses to produce tomatoes and peppers (and a lot more).

The trouble with greenhouse-grown produce from the Netherlands is that the taste of the vegetables are a pale imitation of what they should taste like.For instance, Dutch tomatoes are watery and bland compared to garden grown tomatoes. Maybe it's because they are picked too green so locally growing could help?

Yes, this is a classic investor trap, which has been covered before on Slashdot [slashdot.org]. I seem to recall another story about seawaterfarms dot com on slashdot, but I can't find it. Anyway, you can see that page in the Wayback Machine and see how it didn't exactly go anywhere.

The big rusting tank they talked about that supposedly gave valuable micronutrients to the plant, maybe says something about the seriousness of the project.

"We" already are starving and overpopulated** [worldhunger.org]. This research project is sponsored by companies operating in a very rich country - has potential to alleviate starvation and in the third world, but it is unlikely that will happen in our lifetimes. The evidence so far strongly suggests that we now live in a "winner-take-all" world economy [slate.com], where technological advances do not filter down and only serve to deepen the inequality both within a countries population and between countries [wikipedia.org]. Your stand on the environment one way or the other has nothing to do with that...

My father remembers sending food parcels in the 1970s from the UK to relatives in mainland China. Now, starvation is almost unknown there. Yet, China was a more equal society in the 1970s -- virtually everyone was extremely poor.

The BBC just ran a piece [bbc.co.uk] on how population growth is slowing, global inequality has been reduced from a stark binary proposition to a continuum, and rates of global literacy are skyrocketing, just for a bit of contrast there.

Some cherry picking going in that BBC article. Here is a better link [wordpress.com]. Here is the data [gapminder.org].

Conclusions

The problems of extreme poverty and population growth (may well) have been solved.
Climate change is still a massive problem (which we must therefore try to solve).
Excessive per-capita resource consumption in rich countries must now be reduced.

The Wordpress blog's conclusions at least, in reality the last problem is the same as the first problem. We use so much energy and resources because we can afford to, if "the rest of the world" had money to compete for those resources we'd have to cut back. And despite what the Greens feel like we do recycle and care about emissions and pollution but we also like our cars and huge houses and big screen TVs and air condition and holidays in exotic places. We're not going to stop until we can't afford to, anyone who thinks the first world is going to voluntarily live like the third world is seriously deluded. Next month I'm going on a long vacation flight and I really want this vacation, I can afford it and no amount of eco-babble is going to make me sorry for the CO2 burn.

Like they're pointing out, people are getting literate. People are getting educated. People are getting better health. People spend less time child-bearing. The rest of the world is trying very hard to take over the first world work and bring down the wage equality between them and us. And of course we hate it, you can see people frothing at the mouth if I mention outsourcing here. But I totally understand the employees who of course would like to undercut a westerner and make a lower, but locally still a very good salary. With the world becoming far more connected you are going to get a lot less screwed just for being born in a third world country and you are going to get much less of a free ride for being born in a first world country. The differences are still huge of course, but there's poor and there's illiterate, seven kids, bad health poor.

if you have a starving and overpopulated population **IN SOME AREAS** - as the link I gave shows we defiantly do - then just because other (richer) areas overproduce food that goes to waste does not change the fact that some areas are starving due to overpopulation. Fix the distribution/tech gap problem to solve this inequality then yes we would not have any starving/overpopulated areas anymore.

The world's countries with highest population density [wikipedia.org] are all amazingly wealthy, and have very low rates of starvation. Compare that to the countries leading in poverty [wikipedia.org] who overwhelmingly have low population densities - no overpopulation issues. It's not overpopulation that's the issue - it's distribution of what the world provides. And that is almost always a political issue - it's best for those in control of the starving masses to KEEP them starving, and as such maintain control...

You might want to look at that list again. When you eliminate the city-states at the top of the list, the top nine are Bangladesh, Palestine, Taiwan, South Korea, the Netherlands, Lebanon, Rwanda, India, Haiti. Taiwan, South Korea, and The Netherlands are obviously doing OK, the others though are not exactly what I would call "amazingly wealthy." Over a quarter of the world's population lives in those listed places and I would hazard a guess that they account for a pretty substantial amount of the povert

I'm just trying to help, do what ever I can for people. Like the world hunger thing, the USA for Africa. isn't that great did you guy's hear the song? Nice song isn't it. Beautiful. I'm like anybody else on the planet I'm very moved by world hunger. I've seen the commercials, those little kids starving. And I think god how cruel you know. You see a little kid out there and I know the film crew could give this kid a sandwich You know the kids not

It's really good to see some one follow through on this. This is excellent.

I've been toying and drawing up plans for very low maintenance solar desal for years. All the same basic components as this. But they have taken a few steps further than I was thinking. I had not worked in humid air as a means of watering plants. It really solves a lot of issues with condensing the water.

Problems like biomass build ups and the effort to clean it. Now that effort is productive as it is harvesting food not just cleaning sludge off the walls.

I really like it.

I had wind to pump salt and fresh water up hill. So that I would have a reserve of each at all times. That way wind could be used to build kinetic energy and store it as raise water mass. Salt water of course to feed the evaporators and to flush waste back out to sea. Fresh for obvious uses.

Something I have struggled with is a solar tracker that would allow a mirror to stayed focused on a water pipe to heat it to near steam to accelerate the evaporation. Something that does not actually require elctro-mechanical input.

Something I have struggled with is a solar tracker that would allow a mirror to stayed focused on a water pipe to heat it to near steam to accelerate the evaporation. Something that does not actually require elctro-mechanical input.

Have you considered a solar trough [wikipedia.org]?
You can get the sun's elevation [sunearthtools.com] and adjust the angle of your trough once every 3-4 days; after all, your pipe is not going to be a hit-or-miss-thread so doesn't need to stay exactly in the parabola focus.

I have considered the trough. But there is so much lost solar radiation this way if you don't have some tracking in place.

Basically I get more solar heat transfer if I just have a glass cover over a shallow pond that is painted black. I just don't get the temperature high enough to create a more efficient evaporation. It's just ends up being slower at a lower temp. Which then results in more biomass growth. I'd like to have close to boiling to hinder algae and such in the solar collector system.

So I'm stuck with a lot of labour with either method. However the construction costs are much lower with the black pond method.

I have been tossing around some ideas on how to automatically adjust the angle using struts that expand and contract with heat. Just need to find the right balance of expansion and contraction I hope to cause the system to angle itself as the sun passes overhead. My current thinking is something like a shock absorber filled with gas. A gas shock could cause contraction or expansion of a joint when cooled. So somehow tying the heated sea water into the system to control it's own angle.

I had some kids in a class I was teaching invent an umbrella that used a closed system of two connected canisters, one on each end. The liquid inside (I forget which) was chosen so that when heated it became *more* dense, causing the sun-ward side to be heavier, turning the umbrella toward the sun. It seems that sort of passive system is possible, if you wanted to go down the invention road.:)

I work in agricultural research (cropping) and I'm a bit curious about those yields. Working on a single crop, that's 250 ton/hectare. For most crops in heavy clay soils the best you can hope to achieve is 8 - 12 (maybe 15 if you're *really* lucky). Now again, that's for crops, not vegetables, but I find it hard to believe that vegetables could yield over 20 times as much. Is this right? Is the weight mostly water? Are they able to grow year round with all the heat? I still find it hard to believe as even if you could get 5 harvests a year (and I'd be surprised if they got more than 3) that's still 50t/ha/harvest.

They got three crops, they have tons of sunlight, and using moist air to keep the plants hydrated is a great idea (especially since plants under intense sunlight tend to keep their stomata wide open), they are saying the yields are equivalent to those in europe.

The vines of these crops are indeterminate, and will flower and produce as long as you take care of them. 12 or 18 months is the typical cycle though. They go though and harvest every day. You can't have indeterminate grains as harvest would be a nightmare. And yes all of thos crops are something like 85-90% water.

Agreed. As a farmer by descent (family's occupation, not mine) that number seems unreasonably high.

Even if that yield is accurate, my next concern would be the sustainability - the amount of nitrogen you'd have to add to the soil to sustain that would be incredible but I guess runoff's not an issue if everything's being held in a closed system.

Isn't the nitrogen needed primarily for the formation of the leaves and vines? These plants would only really need a lot of nitrogen in the initial growth phases. Once they are fully grown they would need relatively little nitrogen to keep producing harvestable fruit.

Vegtables like tomatoes in greenhouses can be very productive. Here in the Netherlands, they get 42 kg/m2 per year, which is 420 metric tonne per hectare. This is pretty advanced stuff though, In Almeria, Spain, the other big Greenhouse concentration in Europe they get about 10-12 kg/m2, a lot less.

A little Googling shows that the Tylka F1 tomatoe variety does 155 to 180 tonnes per hectare (70 - 80 tons per acre). With a harvesting period of 4-6 months with maturity 75 days after planting. So only need two crops a year to get a 250 ton per hectare yield which makes it look perfectly feasible to me. If you really work in agricultural research you need to sack yourself!

This tech seems to only addresses the issues of water and heat, not arable soil. It doesn't say either way explicitly, but the fact it was funded by fertilizer companies leads me to believe as much. So this could mitigate some of the impacts of climate change in costal drought-stricken regions, but won't address the nitrogen crisis.

Does anyone know how arable deserts in the middle east or africa are if they were irrigated? Are they mostly untapped reserve of nutrients, or a bunch of sand?

How will they fertilize this? Are they using desert ground, or are they just using the location and using fertile ground or hydroponics? I know that Australia's attempt to irrigate desert ground to grow crops turned whole regions so saline that even desert plants won't grow there anymore.

It's a common misconception that you need fertilization. If you plant the right crops together, they feed each other the nutrients and take care of nitrogen fixation. The catch is that with intermixed crops, it can become more difficult to harvest your crops with bulk thrashers, but robotics and image recognition can come to the rescue on this front.

The are using desal water from evaporation. Very low in Salts. If not zero. They are also in a green house not open field. If the soil gets contaminated with salt they can simply dump it into the sea. Which would not be a bad way of sinking some carbon come to think of it.

In Australia water the desert just results in evaporation of the water. Which leaves behind salt on the land. It was not well thought out.

There isn't a worry here about salination of the soil because the salts end up in the evaporation columns. I saw a lo-tech version of this described a couple of years ago at the UK Plant Sci conference, and this project sounds like an outgrowth from that - they also described the effect on the land outside the greenhouse, with spontaneous growth of native desert flora due to the increased external humidity. The experimenters used a greenhouse with a cardboard wall on the upwind side - the sea water soaks up the wall and is evaporated into the greenhouse by the wind, leaving the salts in the cardboard. After a few years the cardboard wall is a very rigid mineral-rich material that you can use for building structures like sheds.

Just as a protip, if you're using any sort of artificial irradiation (eg not sunlight) you're not organic at all by USDA definitions. Most people that grow indoors or even in light-supplemented greenhouses don't realize this.

Yes, the organic certification is pure marketing, and has no basis in science. Science only recognizes one definition - contains carbon. Organic got usurped because 'All-Natural' couldn't command the price premium in the market

I think organic food is a big waste of money (no scientific evidence it's any healthier)...

But when is "artificial irradiation" being used? I suspect the same people who waste money buying organic are the same ones that freaked out over irradiation. If they hadn't, we wouldn't have so many food contamination issues. (i.e. if the food was irradiated, it would be healthier and not have e. coli, etc.)

"To the people whose labors go beyond ideas into the realm of 'real materials'- to the dry-land ecologists, wherever they may be, in whatever time they work, this effort at prediction is dedicated in humility and admiration."
âFrank Herbert

Not accounting for the usability of this exact piece of science in a practical setting, we will develop further. I salute you guys, you're the thankless people who are doing actual work making this world a better place. Thank you.

This is a great initative that could be be beneficial and hunger suppressing in multiple sandy countries in northern africa and the middle east. As long as the country borders on the sea. Sadly this leaves out Mali, Niger and a few more landlocked piss-poor countries in the regio.

Ideally this would be combined with careful irrigation and planting strategies to stop the desertification (if that is a word). Such a more classic initiative worked well in one of these countries (I forgot which one), but a civ

The US population growth is flattening, as are most other industrial countries. Education has turned out to be the most effective means of birth control. The least-educated segments of the population drive the vast majority of population growth.

I forget all the details at this point, but I remember that the Israelis had a huge number of similar greenhouses in Gaza - thousands of them - that were responsible for something like 15% of total Israeli agricultural output. Fresh vegetables grow well in greenhouses. (Taste may be a different matter...)

I actually read the first paragraph or two of the original article (I know, that's *so* unslashdot), and that's rather clever: seawater over a grid to evaporate and cool, increasing the humidity.. and cooler seawater to cause some of it to condense... providing desalinated seawater.